Merkel cell carcinoma: assessing the effect of wide local excision, lymph node dissection, and radiotherapy on recurrence and survival in early-stage disease--results from a review of 82 consecutive cases diagnosed between 1992 and 2004.

BACKGROUND: Wide surgical excision, lymph node dissection, and radiotherapy have been used with varying efficacy in the management of early-stage Merkel cell carcinoma.
METHODS: Records of 82 patients with early-stage Merkel cell carcinoma between 1992 and 2004 were reviewed.
RESULTS: Forty-two patients developed a recurrence, and 44 died during the study period. Twenty-nine patients presented with regional lymph node disease, which was independently associated with diminished survival (hazard ratio [HR], 4.08; 95% confidence interval [CI], 1.55-10.75; P = .005). Lymphadenectomy was independently associated with prolonged disease-free survival (median, 28.5 vs. 11.8 months; HR, .46; 95% CI, .22-.94; P = .034) but not overall survival (P = .25). Margin-negative excision of the primary tumor (60 of 73) was not significantly associated with either prolonged disease-free survival (median, 16 vs. 14 months) or overall survival (median, 54 vs. 34 months). Forty-eight patients received radiotherapy: 36 to the primary site and 31 to the regional lymph nodes. Radiotherapy to both sites was associated with a longer median time to first recurrence (primary site, 24.2 vs. 11.8 months; regional lymph nodes, 46.2 vs. 11.3 months) and survival (primary site, 53.9 vs. 45.7 months; regional lymph nodes, 103.1 vs. 34.2 months). Administration of any radiotherapy was significantly associated with a prolonged time to first recurrence (HR, .39; 95% CI, .20-.75; P = .004) and survival (HR, .39; 95% CI, .18-.82; P = .013) on the Cox regression multivariate analyses.
CONCLUSIONS: Adjuvant radiotherapy to the primary site after surgical excision is recommended in early-stage disease. Involved regional lymph nodes should be treated with radiotherapy with or without lymphadenectomy.